compiler: base loongarch float abi on target.abi rather than cpu features

src/codegen/loongarch/abi.zig

@@ -49,12 +49,11 @@ const Classifier = struct {
                 .loongarch32 => 32,
                 .loongarch64 => 64,
             },
-            .frlen = if (target.cpu.has(.loongarch, .d))
-                64
-            else if (target.cpu.has(.loongarch, .f))
-                32
-            else
-                0,
+            .frlen = switch (target.abi) {
+                .gnusf, .muslsf => 0,
+                .gnuf32, .muslf32 => 32,
+                else => 64,
+            },
         };
     }
 

src/link/Elf2.zig

@@ -5704,11 +5704,10 @@ fn initHeaders(
             ehdr.shoff = 0;
             ehdr.flags = switch (machine) {
                 .LOONGARCH => .{ .loongarch = .{
-                    .base_abi_modifier = mod: {
-                        const cpu = comp.getTarget().cpu;
-                        if (cpu.has(.loongarch, .d)) break :mod .d;
-                        if (cpu.has(.loongarch, .f)) break :mod .f;
-                        break :mod .s;
+                    .base_abi_modifier = switch (comp.getTarget().abi) {
+                        .gnusf, .muslsf => .s,
+                        .gnuf32, .muslf32 => .f,
+                        else => .d,
                     },
                     .abi_extension = .base,
                     .abi_version = 1,